Electric starter mechanism for small gasoline engines

ABSTRACT

This small engine starting apparatus employs an overriding clutch and a quick disconnect connection for an external electrical power unit; the overriding clutch being engageable, for instance, through the engine crankshaft, flywheel, or alternatively through the power drive to the wheels of a power driven lawn mower or the like; the power unit being safely restrained against reverse torque by attached torque resisting means, and the clutch being coupled, in the deluxe combination, also with a hand pull starter mechanism including a second overriding clutch means in particular relationship to the other overriding clutch in order to enable alternative hand or power starting.

- United States Patent Clarence J. Hekler R.R. #2. Springport. Mich. 49284 [211 App]. No. 796,094 [22] Filed Feb. 3, 1969 [45] Patented Aug. 3, I971 [72] Inventor 1 [541 ELECTRIC STARTER MECHANISM FOR SMALL GASOLINE ENGINES 5 Claims, 11 Drawing H5 [52] U.S. 123/179 SE 51 111:. c1 F02n 17/00 [50] Field oISearch 123/1790,

. 179P,179S,l85B1;74/6

[56] References Cited UNITED STATES PATENTS 2,293,786 8/1942 Worden 64/29 2,831,352 4/1958 I 74/6. 2,939,448 6/1960 Hansen 1 123/179 3,040,854

6/1962 Rauhz,

' 3,437,083 4/19 9 Hamman FOREIGN PATENTS 7 111,092 12/1917 GreatBritain 23/179 872,930 123/179 6/1942 France Primary Examiner-Mark M. Newman Assistant Examiner-Ronald B. Cox Attorney-Roy A. Plant ABSTRACT: This small engine starting apparatus employs an overriding clutch and a quick disconnect connection for an extemal electrical power unit; theoverriding clutch being engageable, for instance, through the engine crankshaft, flywheel, or alternatively through the power drive to the wheels of a power driven lawn mower or the like; the power unit being safely restrained against reverse torque by attached torque resisting means, and the clutch being coupled, in the deluxe combination, also with a hand pull starter mechanism including a second overriding clutch means in particular relationship to the otheroverriding clutch in order to enable alternative hand or power starting.

PATENTED AUG 3 IBYI sum 1 BF 3 lNVENTOR CLARENCE J.HE|SLER ATTORNEY PATENTEDAUB 3:971 3,596,647

SHEET 2 [IF 3 i '16 7 22 m 7 60 45 INVENTOR j CLARENCE J HEISLER lib-J i% Q @[at' ATTORNEY ELECTRIC STARTER MECHANISM FOR SMALL GASOLINE ENGINES BACKGROUND OF THE INVENTION horsepower units. These are used widely for powered yard im-' plements such as mowers, lawn rakes, garden tractors, and the like. Under most conditions, such engines can be readily started with and pull-type mechanism so that it is completely unnecessary to have an expensive and complex power starter on the equipment. l-Iowever, periodically, due to engine con:

ditions, weather conditions, or the like, such small engines are.

extremely difficult to start, causing tremendous physical exertion and frustration. Yet, it is wasteful to have aiiexperisive starter on each piece of powered yard equipment just for these periodic occasions. 1"

Various efforts have been made to develop adapters enabling an external power source such as an electrical drill motor assembly to be attached to a convertedsniall nginefor starting it. These normally require complete conversion of the engine from a hand starting unit. None has been thoroughly satisfactory, as far as is known, in spite of the obvious need. It is desirable to be normally able to start such engines by hand, rather than being always dependent on an electrical outlet and yet be able to employ power starting whenever desirable.

A further difficulty of prior attempts to use a temporarily engaged power unit is that of controlling the power supplying unit under the tremendous reverse torque it causes under conditions of operation. Children and women are probably the ones most likely to need the power unit to start-the engine, and they are the very ones most likely to have trouble s'afely controlling the rotary thrust of the auxiliary power unit when turned on.

SUMMARY OF THE INVENTION It is one object of this invention to provide apparatus for power starting of small engines," while, if desired, enabling the usual hand pull starter to be alternately employed, and also enabling a power unit to be temporarily engaged to start the engine when necessary, with the engagement and disengagement being quick and simple. With this power unit the hand starter mechanism is not disrupted, and the adapter components are relatively inexpensive and completely practical. A

pair of overriding clutches are specially employed in the combination of the hand start mechanism with the power start adapter mechanism to achieve these results.

Another object of the invention is to provide apparatus for either regularly or periodically power starting small engines, safely, with an engageable-disengageable power unit, such as an electric drill assembly, without danger or difficulty from the reverse torque of the engaged power unit. Torque resisting attachments, as one feature of the invention, restrain the engaged power unit under power application to enable the safe use of the combination.

These and other objects, features, and advantages will become apparent from the following specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view showing the major components of a simplified removable embodiment of the in FIG. la shows a fragmentary modification of the FIG. 1 as sembly with a plain, fixedly anchored, pull rope starter pulley incorporated in same.

FIG. 2 is a perspective view of another form of the combination of a power lawn mower and removably attached power starting unit of this invention.

FIG. 3 is a plan view of the torque restraining component in the assembly shown in FIG. 2. v

FIG. 4 is an elevational view taken on plane IV-IV of FIG. 3, looking in the direction of the arrows.

FIG. 5 is a sectional view taken on plane V-V of FIG. 3, looking in the direction of the arrows.

FIG. 6 is a sectional view taken on looking in the direction of the arrows. I

FIG. 7 is an enlarged fragmentary sectional elevational view taken on plane VII-VII of FIG. 2, looking in the direction of the arrows. g

FIG. 8 is an elevational view of a modified form of the torque restraining means shown in FIG. 4.

FIG. 9 is a top plan view showing another embodiment of the present invention. 1

FIG. 10 is an enlarged fragmentary elevational view of a portion of the apparatus shown-in FIG. 9, taken on plane X-X in FIG.-] 1, looking in'the direction of the arrows.

FIG. 11 is a fragmentary, enlarged, partially sectioned view of a portion of the apparatus shown in F IG; 9, taken on plane XI-Xl thereof, looking in the direction of the arrows.

plane VI-VI of FIG. 5,

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the first embodiment which is illustrated in FIG. 1, the invention is illustrated for use preferably with respect to a-motorized lawn mower vehicle of the general type shown in FIG. 2, but with the pull rope starter removed, while FIG. Ia shows a fixed p'ull rope starter pulley 11 incorporated in same. Although this represents a highly simplified potential form of usage of the concept with the motor arranged for starting with an electric drill unit, such concept could well be used with alternative type internal combustion engine powered equipment, two types of which are shown in FIGS. 2 and 9. The assembly I0 illustrated in FIGS. 1 and 1a, when used with a power driven lawn mower, as illustrated in FIG. 2, includes a mower housing 12 having an upper platform portion 12, all mounted on a plurality of rotational supporting wheels 14, and controlled by upwardly projecting handle means 16 of conventional type. Internal combustion engine 20 is mounted on top of platform 12 by suitable means such as cap screws or studs (not shown) and includes the conventional components such ascylinder, piston and piston rod assembly, ignition apparatus, fuel tank, and the like, all of which are so conventional in internal combustion engines as to not require detailed showing thereof herein. It drives a rotary mower blade (not shown) under platform 12'. The engine drives a flywheel 22 (FIG. 7) preferably adjacent the top thereof in normal fashion, inside a flywheel cover 24.

The simplified starting assembly shown in FIGS. 1 and 1a, utilizes the conventional internal combustion engine 20 having a crankshaft 48 with extending end portion 48a adapted to fit into the bottom of an overriding clutch assembly 37 which has an extension portion 38, preferably of squared or polygonal shape adapted to slidably fit into the polygonal socket 50a of adapter '50. The shank of adapter 50 is of a size to fit into and be gripped by chuck 52a of electric drill 52. In operation of the assembly with the overriding clutch assembly engaging end 48a of crankshaft 48, the starting of the electric drill 52 will cause the overriding clutch unit 37 to grip and rotate crankshaft 48 to start motor 20. When motor 20 starts it releases the overriding clutch so that adapter 50 and electric drill 52 may be removed leaving motor 20 running. The FIG. la construction involves converting the common pull rope starter pulley including assembly to one enabling-the use of an electric drill 52 for starting the engine.

Referring now to the alternate construction shown in FIGS. 2 and 7, there is shown attached to the top of flywheel cover 24 adjacent flywheel 22, a manual starting subassembly 26 which includes a cover or housing 28 having legs 28' attached to flywheel cover 24 by welding or otherwise. The manual starting mechanism 26 is positioned atop opening 24' in cover 24 over the center of flywheel 22.

Hand start subassembly 26 includes pulley 30 around which the pull rope 32 is wound, with the inner end of the rope being attached to this pulley, and the outer end having a handgrip member 34 secured thereto and extending from housing 28. A torsional rewind spring 36 engages housing 28 at its outer end 36', and is secured (on its inner end) to an axially extending collar portion 30' of pulley 30. Pulley 30 has an axial passage 30a extending therethrough to receive shaft extension 38 that protrudes therethrough and through a suitable opening 28a in housing 28. A conventional roller type overriding clutch 40 or the like operably engages the shaft extension 38 to pulley 30 by being positioned around the periphery of shaft extension 38 and inside collar 30'. The operation of this will be explained more fully hereinafter.

Pulley 30, FIG. 7, rests upon and is rotational with respect to flywheel 22 by having its lower annular surface 30b resting on an annular cover plate 31 which is in turn secured to the flywheel 22 by capscrews 44. Operably engaged between the outer periphery of lower enlarged end 38a of shaft extension 38 and the inner periphery of an annular upstanding collar 22a and adjacent recess 22b in flywheel 22, is a second roller type overriding clutch unit 45. Flywheel 22 is keyed by a suitable key 46 to crankshaft 48. Shaft extension 38 may be suitably aligned with the upper end of crankshaft 48 by having a central recess 38b on its lower end freely receiving an upper end protrusion 48a on the crankshaft.

The upper end 38c, FIG. 7, of shaft extension 38 is preferably of polygonal cross sectional configuration to fit within a correspondingly shaped polygonal socket 500 on the lower end of an adapter 50, FIG. 1, the upper end of which is in the form of a shank portion to fit within the chuck jaws 52a of an external power unit such as an electrical drill 52.

Power unit 52, FIG. 2, is restrained against reverse torque motion when in operation by torque restraining means 56. This restraining means may constitute a bracket mechanism such as an elongated, rigid rod configurated for example as illustrated in FIGS. 2 through 6. Its terminal ends may be mounted to platform 12' by means of suitable fasteners 58, (or alternatively to some other part of the structure, such as to the engine), the bracket extending upwardly and then laterally above housing 28 where the bracket 56 has a generally U- shaped configuration to receive the body of power unit 52. The particular shape of the inner periphery of this U-shaped portion is preferably preformed to match the peripheral configuration of conventional power units 52 such as an electrical drill motor assembly 52. Obviously, this configuration may vary, provided that it intermeshes with the housing of the power units sufficieritly to prevent the power unit from rotating during the starting operation. In this U-shaped form, it receives the power unit between the legs of the bracket. The upper end of the legs may be clamped together by a releasable spring clip 60 which may be pivotally attached to one leg and snapablc over the other leg as illustrated in-FIGS. 2 and 4. Securement of this clip draws the legs of the bracket closer together to tightly grip the periphery of power unit 52. The bracket is preferably provided with a resilient, compressible coat 56a to grip the power unit, such coat preferably also having a relatively high coefficient of friction to prevent slippage between it and the power unit.

The particular configuration of this torque restraining means 56, FIG. 2, may vary considerably, as noted above, and may take different forms, one of which is illustrated for example, in FIG. 8. In this particular form 156, the unit has depending legs and connectors 158 for attachment to the mechanism, such as on upper platform portion 12' of the motor housing 12, and an upstanding leg portion 158 with a preferably resilient coating 156a to engage one handle of a power drill, some forms of which have a single handle while others have a T-shaped handle which is a common form for a heavy duty power drill, for example.

In operation, the small engine illustrated may be started manually, or if difficulties arise during starting, may be power started. Specifically, manual starting of the engine is done in conventional fashion by pulling on handle member 34, FIG. 7, of pull rope 32. This rotates pulley 30, against the bias of helical spring 36 which winds up as the rope is pulled from the pulley. Rotation of pulley by rope 32 engages overriding clutch 40 to rotate shaft extension 38. Rotation of shaft extension 38 in turn engages overriding clutch 45 to forcibly rotate flywheel 22 and with it engine crankshaft 48. If the engine fires and starts, the speed of the flywheel 22 will be faster than the rate of rotation of pulley 30, so that the overriding clutch 40 disengages to allow the engine to operate freely, and enabling spring 36 to rotate pulley 30 and rewind pull rope 32 when member 34 is allowed to return to its initial position. In this instance of manual start, adapter 50 and power motor 52 are not drivingly actuated, though they may be engaged with the apparatus ready for use if needed. If, however, because of engine difficulty or whatever, it is desired to employ a power start, this can be done by positioning power drive unit 52 inside the legs of U-shaped bracket 56, clamping spring clip 60 over to pull the legs from the dotted line position in FIG. 3 to the solid line position and effectively grip the drill housing, plugging in cord 53 of the drill in a suitable outlet (not shown), and actuating the trigger of the drill. The reverse torque applied to the drill housing is restrained by bracket 56 so that the torque of the drill power unit will not cause it to spin out of the hands of the user. Rather, the force is applied through adapter 50 to shaft extension 38 and hence through overriding clutch 45 to flywheel 22 and crankshaft 48. The bearing surface 300 beneath the bottom of pulley 30 and the top of the cover or clutch retention plate 31 enables the flywheel assembly 22 to rotate without rotating pulley 30, while the spinning of shaft extension 38 within overriding clutch 40 prevents the shaft from rotating the pulley. Power unit 52 can be operated until the engine fires and starts effectively. As soon as it does, so that flywheel 22 rotates at a faster rotational rate than the power unit, overriding clutch 45 will disengage so that the power unit can be conveniently retracted and removed, if desired, without difficulty.

In FIGS. 9 through 11 is shown another embodiment wherein the assembly 100, illustrated in the form of a selfpropelled lawn mower, has an internal combustion engine 102 which not only drives the mower blade, but also has a power output or power takeoff unit connected to drive the front axle through a belt and gear drive unit. In this embodiment, the power unit for starting the engine can be operably engaged with the power takeoff to the wheel drive.

As previously, assembly 100, FIG. 9, includes a mower housing 104 with an upper platform 104 upon which engine 102 is mounted. The engine includes a manual start and rewind mechanism 106, and also includes a gearbox 108, FIG. 11, through which an output shaft is driven in conventional fashion for a power takeoff. A sheave 112 is mounted on shaft 110 and drives a belt 114 which also encircles a second sheave 116 on rotational mounting pin 118. Sheave 116 is a part of a double sheave which includes portion 116a as well, driving a second belt 119 which in turn drives sheave 120, FIG. 9, mounted on shaft 121 carrying a helical gear (not shown) rotated by sheave for driving a spur gear 122 conventionally mounted on the front axle of the unit for rotating same and driving assembly 100. This double-sheave assembly can, if desired, be externally rotationally driven by an attached temporarily engaged power unit through a connection, such as illustrated in FIG. 11. More specifically, adapter 132 has a shank receivable in chuck 130' of power unit 130, and having a polygonal socket.132' which engages the polygonal upper end 134' of fitting 134. The lower end of this fitting includes an overriding clutch 136, with the central portion of this clutch being conventionally secured to the upstanding stud 138 extending axially from the double-sheave unit 116-1160. The outer portion of overriding clutch 136 being drivingly connected to fitting 134 when adapter 132 is spun by power unit 130.

A reverse torque restraining bracket means 140, FIG. 9, is used and which may take the form of a pair of spaced generally parallel straddle legs 140a and 140b, FIG. 10, mounted by bracket elements 141a and 14lb to the engine 102. The central portions of these may be coated with a resilient compressible cushioning material 140' to better grip and hold power unit 130. A spring clip member 142 may be employed to force the legs into secure engagement with power unit 130 as illustrated in FIG. 10.

With the unit shown in FIGS, 9 through 1 1, this engine may be manually started by the rewind type pull rope mechanism 106 or alternatively, with a power unit, such as an electric drill 130, may be positioned so that the polygonal end 132 of adapter 132 fits over the polygonal upper end 134' of fitting 134 of the overriding clutch unit 136. When the power unit 130 is in place, spring clip 142 secures it effectively. Hence, by actuation of the power unit, the engine can be driven through gearbox 108 to start the engine. Once it is started, the overriding clutch 136 releases, enabling the power unit to be removed if desired.

The embodiments of the invention in which I claim an exclusive property or privilege are defined as follows:

1. An apparatus for starting small engines having a crankshaft carrying a flywheel, comprising: shaft extension means; an overriding clutch operably connecting said shaft extension means to said flywheel for use in rotating the latter a rotational power unit; and an adapter means for said shaft extension means to engage said rotational power unit thereto to start said engine, restraining means for rotationally restraining and stabilizing said power start unit; said restraining means comprising a bracket having portions straddling said power unit and clampingly securing said power unit in a position in which said adapter means is connected to the shaft extension against separation, and quick connection and release means to urge said portions straddling said power unit into clamping engagement with said power unit; means for anchoring said bracket in operable position, and resilient means to cushion the reverse torque force delivered by said power unit to said restraining means when said power said bracket in operable position, and resilient means cushion the reverse torque force delivered by said power unit to said restraining means when said power unit is actuated.

2. Apparatus for starting a small engine having a crankshaft carrying a flywheel, comprising hand pull torque means having an opening therethrough; shaft extension means having an exposed end; a first overriding clutch operably connecting said shaft extension means and said flywheel; a separate detachable rotary power unit; adapter means for releasably connecting said power unit to the exposed end of said shaft extension means with one of said adapter means and shaft extension means extending through said opening of said hand pull torque means; and a second overriding clutch operably connecting said hand pull torque means and said shaft extension means; said first and second overriding clutches transmitting torque resulting from operating said hand pull means to said flywheel whereby, both said clutches are actuated when said hand pull means is operated; and said first clutch transmits torque resulting from rotation of said shaft extension means by said power unit without engaging said second overriding clutch.

3. Apparatus for starting a small engine having rotational drive components including a flywheel, comprising: shaft ex tension means at a location offset from said flywheel and having an exposed end; drive means connecting said shaft extension means to said fly wheel, said drive means including first overriding clutch means remote from the flywheel, whereby, the flywheel is rotated in response to rotation of said first shaft extension means; hand pull torque supplyin rneans; drive means connecting said hand pull torque supp ylng means to said flywheel, said drive means including a second overriding clutch means remote from said first overriding clutch means and having an axis of rotation different from the axis of rotation of said first overriding clutch means; a separate detachable rotary power unit; and connector means on said rotary power unit connectable with said exposed end of said shaft extension means to transmit torque from said power unit to said flywheel via said shaft extension and first overriding clutch means.

4. The apparatus of claim 3 wherein said first overriding clutch means has an axis of rotation parallel with the axis of rotation of said second overriding clutch means.

5. The apparatus in claim 2 wherein said adapter means comprises a coupling having an elongated shank on one end and a polygonal socket on the other end, said shaft extension means having a polygonal end operably fitting said socket.

33 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 596, 647 Dated August 3, 1971 Inventor(s) Clarence J. Heisler It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 18, "and" should read ---a hand--. Column 2, line 51, before "cylinder" insert ----a Column 5, line 32, after "rotating the latter" insert a semi-colon starting at line 45 and ending at line 2 of column 6, cancel "said bracket in operable position, and resilient means cushion the reverse torque force delivered by said power unit to said restraining means when said power".

Signed and sealed this 2nd day of May 1972.

(SEAL) Attest:

EDWARD M.FLEI'CHER, JR. ROBERT GOITSCHALK Attesting Officer Commissioner of Patents 

1. An apparatus for starting small engines having a crankshaft carrying a flywheel, comprising: shaft extension means; an overriding clutch operably connecting said shaft extension means to said flywheel for use in rotating the latter a rotational power unit; and an adapter means for said shaft extension means to engage said rotational power unit thereto to start said engine, restraining means for rotationally restraining and stabilizing said power start unit; said restraining means comprising a bracket having portions stRaddling said power unit and clampingly securing said power unit in a position in which said adapter means is connected to the shaft extension against separation, and quick connection and release means to urge said portions straddling said power unit into clamping engagement with said power unit; means for anchoring said bracket in operable position, and resilient means to cushion the reverse torque force delivered by said power unit to said restraining means when said power said bracket in operable position, and resilient means cushion the reverse torque force delivered by said power unit to said restraining means when said power unit is actuated.
 2. Apparatus for starting a small engine having a crankshaft carrying a flywheel, comprising hand pull torque means having an opening therethrough; shaft extension means having an exposed end; a first overriding clutch operably connecting said shaft extension means and said flywheel; a separate detachable rotary power unit; adapter means for releasably connecting said power unit to the exposed end of said shaft extension means with one of said adapter means and shaft extension means extending through said opening of said hand pull torque means; and a second overriding clutch operably connecting said hand pull torque means and said shaft extension means; said first and second overriding clutches transmitting torque resulting from operating said hand pull means to said flywheel whereby, both said clutches are actuated when said hand pull means is operated; and said first clutch transmits torque resulting from rotation of said shaft extension means by said power unit without engaging said second overriding clutch.
 3. Apparatus for starting a small engine having rotational drive components including a flywheel, comprising: shaft extension means at a location offset from said flywheel and having an exposed end; drive means connecting said shaft extension means to said fly wheel, said drive means including first overriding clutch means remote from the flywheel, whereby, the flywheel is rotated in response to rotation of said first shaft extension means; hand pull torque supplying means; drive means connecting said hand pull torque supplying means to said flywheel, said drive means including a second overriding clutch means remote from said first overriding clutch means and having an axis of rotation different from the axis of rotation of said first overriding clutch means; a separate detachable rotary power unit; and connector means on said rotary power unit connectable with said exposed end of said shaft extension means to transmit torque from said power unit to said flywheel via said shaft extension and first overriding clutch means.
 4. The apparatus of claim 3 wherein said first overriding clutch means has an axis of rotation parallel with the axis of rotation of said second overriding clutch means.
 5. The apparatus in claim 2 wherein said adapter means comprises a coupling having an elongated shank on one end and a polygonal socket on the other end, said shaft extension means having a polygonal end operably fitting said socket. 